THE FRUCTIFICATION 49 



the Perisporiacei, after the contact of two hyphae, a process 

 is evolved from each, which ultimately develops respectively 

 into oocyst and antheridium. De Bary from this traced the 

 history of a conceptacle in Erysiphe to its completion ; and 

 expressed the opinion that the perithecia and asci of many of 

 the Ascomycetes originated, and were perfected, in the same 

 manner. 



Other perithecia, with the same external form, hahit, and 

 texture, but with stylosporous fructification, are included 

 systematically in the Sphaeropsideae. There are no asci and no 

 paraphyses present, but the receptacles enclose an indefinite 

 number of sporules, which are generated singly at the apices 

 of very short slender threads. These some have called basidia, 

 but that is a misnomer, since in the Basidiomycetes it is 

 accepted with a different interpretation. In the Sphaeropsideae 

 the delicate supporters of the sporules are simply sporo- 

 phores. The sporules themselves do not differ materially 

 in form, size, and appearance from the sporidia which are 

 generated in asci, and there is a suspicion that some of them 

 are genetically connected, but in what manner has never been 

 ascertained. 



In some genera the perithecia are nearly obsolete where 

 the species are immersed, or else they are so fused with the 

 matrix as not to be distinguishable, or they 

 may be quite spurious, so that cavities in 

 the matrix perform all the functions of 

 perithecia (Fig. 30). The latter condition 

 prevails in the Melanconieae, where the FlG 30 _g pur i ous 

 conidia are produced, as in the Sphaeropsideae, perithecium of Mel- 

 on short conidiophores within definite cavities 

 or cells, the walls of which are differentiated from the matrix. 

 There is a basal cushion or spore -bed which is formed from 

 the mycelium, and this spore -bed originates the conidia. 

 Saccardo and the majority of systematists apply the term 

 "conidia" to the spore -like vesicles of the Melanconieae as 

 well as to the Hyphomyceteae or moulds. 



A small but interesting group of Fungi, having the habit 

 and appearance of moulds, differ from them very materially 

 in possessing a receptacle at the apex of the carpophore, which 



4 



